Which of the following research designs will allow cause-and-effect conclusions?
A. correlational studies
B. experimental
C. quasi-experimental
D. archival research
The correct answer and explanation is:
Correct Answer: B. Experimental
Explanation:
Among the research designs listed—correlational studies, experimental, quasi-experimental, and archival research—only the experimental design can reliably establish cause-and-effect relationships between variables.
In experimental research, the investigator manipulates one variable (the independent variable) and observes the effect on another variable (the dependent variable) while controlling for extraneous variables. This is typically achieved through random assignment, where participants are randomly assigned to either the treatment or control group. Random assignment helps ensure that any differences in outcomes are due to the manipulation of the independent variable, not other factors.
For example, if a researcher wants to test whether a new teaching method improves student performance, they could randomly assign students to two groups—one using the new method and one using the traditional method. If the group using the new method performs significantly better, the researcher can reasonably infer that the teaching method caused the improvement.
In contrast:
- Correlational studies examine relationships between variables but do not involve manipulation or control, making it impossible to determine causation. A correlation between ice cream sales and drowning incidents, for instance, does not imply one causes the other; both may be linked to a third variable, like hot weather.
- Quasi-experimental designs involve manipulation of variables but lack random assignment, which limits the ability to infer causality due to potential confounding variables.
- Archival research involves analyzing existing data or records. While useful for identifying patterns, it is observational and cannot establish cause-and-effect due to the lack of control over variables and experimental conditions.
Therefore, experimental design is the gold standard for determining causal relationships in research.